The trial of an alleged serial arsonist gives me my second opportunity on this blog (here was the first), to address reverse Rule 404(b) evidence, which is convenient because I just addressed this type of evidence in class today.

Raymond Lee Oyler, 38, faces five counts of first-degree murder in connection with a 41,000-acre Esperanza fire that killed five U.S. Forest Service firefighters and destroyed 34 homes. He also faces multiple counts of arson and possessing destructive devices for numerous prior brush fires and could face the death penalty if convicted. Specifically, Oyler is accused of setting 23 fires between May and October 2006, culminating in the Esperanza fire.

And Oyler's case was hindered to a significant extent by two recent occurrences. First of all, "California Department of Justice criminalist Marianne Stam testified Thursday that matches recovered from two June 2006 arson fires were chemically and dimensionally comparable to matches plucked from a box of matches submitted as evidence in the Olyer case.

Secondly, while Oyler's attorney, Mark McDonald, tried to present evidence that a former federal firefighter facing arson charges in Los Angeles County started at least some of the blazes, Judge W. Charles Morgan ruled that evidence inadmissible. Unfortunately, the article on the trial doesn't give any details about this ruling, but I don know that Oyler should not have been per se precluded from admitting this evidence.

"evidence that a person committed a crime, civil wrong, or other act [is admissible] when relevant to prove some fact (such as motive, opportunity, intent, preparation, plan, knowledge, identity, absence of mistake or accident, or whether a defendant in a prosecution for an unlawful sexual act or attempted unlawful sexual act did not reasonably and in good faith believe that the victim consented) other than his or her disposition to commit such an act."

Now, usually, it is the prosecution presenting evidence of a prior act by a criminal defendant, such as the prosecution presenting evidence of a defendant's prior arsons to prove that he had a common plan or scheme for committing such crimes. However, as I noted in my previous post, "[d]efendants can also use the Rule to introduce so-called reverse 404(b) [or here, reverse Rule 1101(b)] evidence, under which the defendant introduces evidence of other acts of someone besides himself to prove that the other person was the likely perpetrator of the crime. United States v. Della Rose, 403 F.3d 891, 894 (7th Cir. 2005)." And indeed, courts are actually more willing to admit this type of evidence because they are less concerned about unfair prejudice to the prosecution than they are about unfair prejudice to the defendant.

That said, I'm assuming that Oyler had insufficient evidence to link the former firefighter to the crimes and/or some permissible purpose, which is why the court deemed this alternate suspect evidence inadmissible.